1. Field of the Invention
The present invention relates generally to a hermetic motor-driven compressor for use in a refrigerator, an air-conditioner or the like, and more particularly to a low noise, hermetic motor-driven compressor.
2. Description of the Prior Art
In recent years, there has been an increased demand for a low noise, hermetic motor-driven compressor (hereinafter referred to, for brevity, as "compressor").
A conventional compressor disclosed in Japanese Patent Laid-open Publication No. 52-130013 includes, as shown in FIGS. 4 through 6, a closed container 1 in which a compressor element 2 and a motor element 3 are disposed as a single combined motor-and-compressor assembly 4. The compressor element 2 is composed of a cylinder 5, a piston 6 reciprocating within the cylinder 5, a crankshaft 7 rotatable in unison with a rotor 3a of the motor element 3, and a connecting rod 8 for translating a rotary motion of the crankshaft 7 into a reciprocating motion of the piston 6.
A tube 9 is welded at its one end to the closed container 1. Numeral 10 is a so-called hermetic terminal hermetically welded to the closed container 1 for supplying electricity to the motor element 3. The closed container 1 has flat bottom wall portions 1a and 1b to which a flat leg 11 is welded. The combined motor-and-compressor assembly 4 is resiliently supported by four snubbers 12 each having a suspension spring 13 acting between the corresponding snubber 12 an the combined motor-and-compressor assembly 4. The snubbers 12 are welded to the flat bottom wall portions 1a and 1b of the closed container 1.
Since the leg 11 and the snubbers 12 are attached by welding to the flat bottom wall portions 1a and 1b of the closed container 1, as described above, the welding work can be performed easily and efficiently.
However, since the stiffness of flat bottom wall portions 1a and 1b is relatively low, the closed container 1 tends to vibrate and thereby produce a noise. At the same time, an operation noise of the combined motor-and-compressor assembly 4 is likely to leak out from the flat bottom wall portions 1a and 1b. Thus, the conventional compressor generates relatively large operation noises and hence cannot meet a severe noise level which is required for modern compressors.